In the new edition, the government says planning permission for opencast or deep-mine development "should not be permitted".

"Should, in wholly exceptional circumstances, proposals be put forward they would clearly need to demonstrate why they are needed in the context of climate change emissions reductions targets and for reasons of national energy security," the policy said.

An effective ban on new coal mines in Wales getting planning permission is to come into effect.

The measure is part of the Welsh Government's new planning policy, published on Wednesday.

Applications for opencast and deep-mine coal mining will only be allowed under "exceptional circumstances".

Environment Secretary Lesley Griffiths said the policy will ensure "we have well-designed spaces which will benefit future generations".

It comes after the assembly passed legally-binding carbon emissions targets on Tuesday.

In the new edition, the government says planning permission for opencast or deep-mine development "should not be permitted".

"Should, in wholly exceptional circumstances, proposals be put forward they would clearly need to demonstrate why they are needed in the context of climate change emissions reductions targets and for reasons of national energy security," the policy said.

"The Welsh Government has set challenging targets for decarbonization and increased renewable energy generation," the document said.

"The continued extraction of all fossil fuels, including shale gas, coal bed methane and underground coal gasification, are not compatible with those targets."